Dual-Function MIMO Radar-Communications Via Frequency-Hopping Code Selection

Intensifying competition over the frequency spectrum has driven the research effort into strategies for coexistence between radar and communications. Strategies for achieving this range from spectrum sharing using cognitive radio techniques to co-design where the radar and communications systems are re-imagined to ensure they do not interfere with each other. In this paper we propose a new signaling scheme for Dual-Function Radar Communications (DFRC) that enables frequency-hopped multiple-input-multiple-output (MIMO) orthogonal radar wave-forms to carry communication symbols. The Frequency-hopping (FH) code is changed from subpulse to another such that the index of the selected code carries the desired symbol. Contrary to recent phase-shift keying (PSK)-based schemes which embed one PSK symbol within each subpulse, the proposed scheme does not suffer from phase-discontinuity and is shown to have better spectral efficiency. We show that the data rate that can be achieved using the proposed scheme is proportional to the size of the FH code, the number of transmit antennas, number of subpulses within a pulse repetition interval, and pulse repetition frequency. Simulations examples are provided to evaluate the performance of the proposed method and demonstrate the effectiveness of this information embedding scheme.